<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        p {
            color: red;
        }

        .red {
            color: blue;
        }

        #blue {
            color: blue;
        }

        * {
            color: blueviolet;
        }
    </style>
</head>
<body>
    <!-- 标签选择器 -->
    <p>这是p标签1</p>
    <p>这是p标签2</p>
    <!-- 类选择器 -->
    <div class="red">这是div</div>
    <!-- id选择器 -->
    <span id="blue">这是span</span>
    <!-- 通配符选择器* -->

</body>
</html>